Various types of devices, such as jigs and gauges, for use in drilling holes are well know, and numerous such devices are shown in the following United States Letters Patent: Nos.
______________________________________ 3,914,871 2,838,966 1,809,768 3,708,237 2,804,788 1,161,479 3,557,641 2,798,520 952,968 3,019,675 2,761,476 917,488 2,987,944 2,651,951 581,811 2,930,263 2,535,450 10,092 2,928,441 2,268,930 Des. 160,734 ______________________________________
While some of the patents show devices having a pair of fixed drill guides, such patents are apparently devoid of any teaching of a device for positioning the guides for drilling parallel pairs of aligned holes in members to be joined to each other, a problem being that in order to position the device properly on the two members there must be corresponding positioning parts on opposite ends of the device, as will become apparent hereinafter.
It is a feature of this invention to provide a device adapted to be releasable secured in fixed position on a first workpiece and then on a second workpiece, the device having corresponding and opposite end positioning portions to be alternately positioned aligned with markings aligned on the workpieces and parallel to the desired axes of the holes to be drilled in the workpieces, the markings being in alignment when the workpieces are laid-out in the orientation in which it is desired that they be joined. Another feature is the device utilizing standard pairs of drill guides of various sizes, the guides being releasable and interchangable in the device.
It is a primary object of this invention to provide a new and useful compact portable dowel hole spacing and drilling device for drilling of parallel pairs of aligned dowel holes in workpieces to be joined to each other, the workpieces having aligned markings in the desired position of joining, and the device having opposite but corresponding positioning portions, one for alignment with the aligned marking on one of the workpieces and the other for alignment with the marking on the other workpiece. A related object is provision of such a device having a U-shaped, rigid base with inner faces of the bight and one of the legs having flat faces perpendicular to each other, the bight having provision for releasably mounting drill guides having their longitudinal axes parallel to each other and to the face of the first leg and equally spaced from this leg, and the positioning portions being on opposite open ends of the U-shaped base and in planes in parallel to each other and perpendicular to the face of the first leg. A further related object is provision on the second leg for clamping the device on the workpiece.
The invention, in brief, is directed to a device adapted to be clamped to a workpiece and when so clamped having provision for guiding a drill in drilling a pair of holes in the workpiece. The device has a rigid U-shaped base with inner faces of the bight and a first leg perpendicular to each other, the base having opposite open end faces so that the workpiece may extend therethrough, and the end faces having provision for positioning the base with axes of adjacent positions for drilling the workpiece equally spaced from the adjacent end. These axes are parallel to each other and to the inner face of the first leg, and are equally spaced from this face. The second leg of the U-shaped base has provision for clamping the device to the workpiece.
These and other features and advantages of the invention will become apparent from the following description and the accompanying drawings.